The Strahler number or Horton-Strahler number of a tree, originally introduced in geophysics, has a surprisingly rich theory. We sketch some milestones in its history, and its connection to arithmetic expressions, graph traversing, decision problems for context-free languages, Parikh’s theorem, and Newton’s procedure for approximating zeros of differentiable functions. 1 The Strahler Number In ...

Traditional supply chain inventory modes with trade credit usually only assumed that the up-stream suppliers offered the down-stream retailers a fixed credit period. However, in practice the retailers will also provide a credit period to customers to promote the market competition. In this paper, we formulate an optimal supply chain inventory model under two levels of trade credit policy with d...

In contemporary communication systems, Turbo coding is an important channel coding method which results in extremely low bit-error ratios (BER) at signal-tonoise ratios (SNRs) within 1 dB off the Shannon Limit. The BCJR algorithm is used as an iterative decoding scheme in Turbo coding. However, it requires that the whole input sequence is received possible including termination. This makes it d...

The Lyapunov stability method is the most popular and applicable stability analysis tool of nonlinear dynamic systems. However, there are some bottlenecks in the Lyapunov method, such as need for negative definiteness of the Lyapunov function derivative in the direction of the system’s solutions. In this paper, we develop a new theorem to dispense the need for negative definite-ness of Lyapunov...

Dataflow languages allow the specification of reactive systems by mutually recursive stream equations, functions, and boolean activation conditions called clocks. Lustre Scade are dataflow for programming embedded systems. programs compiled a succession passes. This article focuses on normalization pass which rewrites into simpler form required code generation. Vélus is compiler from normalized...

This thesis presents some novel results on the cryptanalysis and design of stream ciphers. The first part of the thesis introduces various stream ciphers design and cryptanalysis techniques. The second part of the thesis gives the cryptanalysis of seven stream ciphers. The properties of addition are exploited in the cryptanalysis of two stream ciphers: the differential-linear cryptanalysis agai...

We consider a finite element method based on biorthogonal or quasi-biorthogonal systems for the biharmonic problem. The method is based on the primal mixed finite element method due to Ciarlet and Raviart for the biharmonic equation. Using different finite element spaces for the stream function and vorticity, this approach leads to a formulation only based on the stream function. We prove optim...

modeling of stream flow–suspended sediment relationship is one of the most studied topics in hydrology due to itsessential application to water resources management. recently, artificial intelligence has gained much popularity owing toits application in calibrating the nonlinear relationships inherent in the stream flow–suspended sediment relationship. thisstudy made us of adaptive neuro-fuzzy ...

In this paper, we study the global existence of steady subsonic Euler flows through infinitely long nozzles without the assumption of irrotationality. It is shown that when the variation of Bernoulli’s function in the upstream is sufficiently small and mass flux is in a suitable regime with an upper critical value, then there exists a unique global subsonic solution in a suitable class for a ge...